Viral-based systems can be modified to present a high density of ligands in a defined symmetric pattern; this type of display can increase the avidity of binding to target biomolecules. For example, bacteriophage lambda has been used for phage display applications through peptide fusions with either the major tail protein (gpV) or the gpD decoration protein (Maruyama et al., 1994; Mikawa et al., 1996). Studies have shown that gpD may be modified at either the N- or C-terminus to present peptides at the capsid surface for phage display applications. However, all current phage based display systems are limited by the required construction of decoration or major capsid protein fusion constructs within the context of an infectious viral particle, while the constructs have been constructed in vivo, thus limiting these systems to peptide and protein fusion constructs expressed within infected cells in the context of an infectious virus. As a result, the stoichiometry of the fusion proteins cannot be controlled on the resulting infectious viral particles, the modified constructs are limited to peptide and protein display ligands, and the fusion proteins are limited to fusions at the N- or C-terminus of the decoration protein.